\centering
\begin{tabular}[t]{lccc}
\toprule
\multicolumn{1}{c}{ } & \multicolumn{3}{c}{Dep var: Chose trans in private outcome round (=1)} \\
\cmidrule(l{3pt}r{3pt}){2-4}
\multicolumn{1}{c}{ } & \multicolumn{1}{c}{\makecell[c]{Drop when others heard\\outcome-round answers\\(3-person discussion sample)}} & \multicolumn{1}{c}{\makecell[c]{Drop when listener spoke\\(Phase 2 sample)}} & \multicolumn{1}{c}{\makecell[c]{Drop when No-discussion (public)\\participants spoke\\(Phase 2 sample)}} \\
\cmidrule(l{3pt}r{3pt}){2-2} \cmidrule(l{3pt}r{3pt}){3-3} \cmidrule(l{3pt}r{3pt}){4-4}
  & (1) & (2) & (3)\\
\midrule
3-person discussion & \num{0.174}*** & \num{0.178}*** & \num{0.179}***\\
 & (\num{2.1e-02}) & (\num{0.031}) & (\num{0.031})\\
 & {}[\num{<0.001}] & {}[\num{<0.001}] & {}[\num{<0.001}]\\
Observer (No discussion, public) &  & \num{0.046}* & \num{0.042}\\
 &  & (\num{0.026}) & (\num{0.027})\\
 &  & {}[\num{0.080}] & {}[\num{0.112}]\\
Non-observer (No discussion, public) &  & \num{0.024} & \num{0.028}\\
 &  & (\num{0.031}) & (\num{0.032})\\
 &  & {}[\num{0.436}] & {}[\num{0.388}]\\
Speaker (2-person discussion) &  & \num{0.141}*** & \num{0.134}***\\
 &  & (\num{0.029}) & (\num{0.028})\\
 &  & {}[\num{<0.001}] & \vphantom{1} {}[\num{<0.001}]\\
Listener (2-person discussion) &  & \num{0.144}*** & \num{0.127}***\\
 &  & (\num{0.034}) & (\num{0.033})\\
 &  & {}[\num{<0.001}] & {}[\num{<0.001}]\\
\midrule
Num. observations & \num{4178} & \num{4364} & \num{4364}\\
Num. participants & \num{2089} & \num{2182} & \num{2182}\\
Num. groups & \num{750} & \num{729} & \num{729}\\
\bottomrule

\end{tabular}

